The present invention relates to a method and apparatus for making X-ray pictures on dielectric receptor or carrier sheets. More particularly, the invention relates to improvements in a method and apparatus for making latent images of X-rayed objects on dielectric receptor sheets in the interelectrode gap of an ionography imaging chamber. Still more particularly, the invention relates to improvements in a method and apparatus for making latent images of X-rayed objects in the interelectrode gap of an ionography imaging chamber which is filled with a compressed high Z gas, such as Xenon, Krypton or Freon. X-rays which penetrate into the imaging chamber produce electrons in the gap, and such electrons cause the development of a latent image on the sheet which lies against one of the electrodes.
Radiographic systems with xerographic printing are disclosed, for example, in U.S. Pat. No. 3,828,192 granted Aug. 6, 1974 to Morsell and in U.S. Pat. No. 3,774,029 granted Nov. 20, 1973 to Muntz et al. A drawback of the patented systems is that the latent image cannot extend close to one or more outer side faces of the imaging chamber. This is due to the fact that the sealing means which is interposed between the sections of the imaging chamber surrounds all parts of the margin of a properly inserted dielectric carrier sheet. Latent images which extend all the way to or into very close proximity of the outer side or sides of the imaging chamber are desirable in many instances, e.g., for radiographic examination of female breasts. As a rule, the physician desires to obtain an image of the entire breast, i.e., also of that portion which is immediately adjacent to the rib cage.